/*-
 *
 *  * Copyright 2015 Skymind,Inc.
 *  *
 *  *    Licensed under the Apache License, Version 2.0 (the "License");
 *  *    you may not use this file except in compliance with the License.
 *  *    You may obtain a copy of the License at
 *  *
 *  *        http://www.apache.org/licenses/LICENSE-2.0
 *  *
 *  *    Unless required by applicable law or agreed to in writing, software
 *  *    distributed under the License is distributed on an "AS IS" BASIS,
 *  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  *    See the License for the specific language governing permissions and
 *  *    limitations under the License.
 *
 */

package org.deeplearning4j.util;

import org.apache.commons.io.FileUtils;

import java.io.*;

/**
 * Serialization utils for saving and reading serializable objects
 *
 * @author Adam Gibson
 */
public class SerializationUtils {

    private SerializationUtils() {}

    @SuppressWarnings("unchecked")
    public static <T> T readObject(File file) {
        ObjectInputStream ois = null;
        try {
            ois = new ObjectInputStream(FileUtils.openInputStream(file));
            return (T) ois.readObject();
        } catch (Exception e) {
            throw new RuntimeException(e);
        } finally {
            if (ois != null)
                try {
                    ois.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
        }

    }

    /**
     * Reads an object from the given input stream
     * @param is the input stream to read from
     * @return the read object
     */
    @SuppressWarnings("unchecked")
    public static <T> T readObject(InputStream is) {
        try {
            ObjectInputStream ois = new ObjectInputStream(is);
            return (T) ois.readObject();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }

    }



    /**
     * Converts the given object to a byte array
     * @param toSave the object to save
     */
    public static byte[] toByteArray(Serializable toSave) {
        try {
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            ObjectOutputStream os = new ObjectOutputStream(bos);
            os.writeObject(toSave);
            byte[] ret = bos.toByteArray();
            os.close();
            return ret;
        } catch (Exception e) {
            throw new RuntimeException(e);
        }

    }


    /**
     * Writes the object to the output stream
     * THIS DOES NOT FLUSH THE STREAMMultiLayerNetwork
     * @param toSave the object to save
     * @param writeTo the output stream to write to
     */
    public static void writeObject(Serializable toSave, OutputStream writeTo) {
        try {
            ObjectOutputStream os = new ObjectOutputStream(writeTo);
            os.writeObject(toSave);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }

    }

    public static void saveObject(Object toSave, File saveTo) {
        try {
            OutputStream os1 = FileUtils.openOutputStream(saveTo);
            ObjectOutputStream os = new ObjectOutputStream(os1);
            os.writeObject(toSave);
            os.flush();
            os.close();
            os1.close();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }

    }
}
